ML20112G506

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Forwards Status of Planned Audit Response to NRC July 1984 Audit of Plant Operations,Per Denton .Repts Covering Technical Details of Listed Subjs Will Be Provided by 850131,per 841128 & 29 Meetings
ML20112G506
Person / Time
Site: Fort Saint Vrain Xcel Energy icon.png
Issue date: 01/04/1985
From: Lee O
PUBLIC SERVICE CO. OF COLORADO
To: Johnson E
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
References
P-85003, TAC-55294, NUDOCS 8501160361
Download: ML20112G506 (11)


Text

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PUBLIC SERVICE COMPANY OF COLORADO P. O. BOX 840 DENVER. COLORADO 8020

" " " " January 4, 1985 Fort St. Vrain l Unit No. 1 P-85003 F

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Regional Administrator @ON D Region IV '

Nuclear Regulatory Commission 611 Ryan Plaza Drive, Suite 1000 JAN gg Arlington, TX 76011 i y

Attn: E. H. Johnson =

SUBJECT:

NRC Audit of Fort St. Vrain Operations

REFERENCE:

NRC 1.etter Denton to Walker, dated October 16, 1984 (G-84392)

Dear Mr. Johnson:

In response to the letter referenced above regarding the July 1984 NRC audit of Fort St. Vrain operations, the attached status of planned audit responses is submitted for your information. Reports covering the technical details on each of the following subjects will be provided to the NRC on or before January 31, 1985 as indicated in the attachment to this letter and requested by NRC staff at the November 28th and 29th meeting between NRC and PSC.

I. Reserve Shutdown System II. CRDOA Instrumentation III. CRD0A Cable Material IV. CRD0A Helium Purge V. CRDM Temperature VI. CRDOA Back-EMF Surveillance A -

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,. -,. . P-85003- Page 2  !

Please contact 'Mr. M. H. Holmes.at(303)571-8409 if you have any

- questions'regarding this material.

Very truly yours,

0. R. Lee, Vice President 4

Electric Production i . .

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STATUS OF PSC RESPONSES TO NRC AUDIT OF FORT ST. VRAIN OPERATIONS The Following Items Should Be Completed Prior to Restart I. Actions Required for Control Rod Problems

a. NRC Finding: Ensure that future scram signals will result in all rods automatically being inserted into the core.

The licensee must identify the failure mechanism and take corrective action for the rods that did not scram; or if the cause cannot be positively identified through examination or analysis of the drive mechanisms and the circumstances of the failure, other compensatory measures must be taken to provide assurance of reliability of control rods. These measures could reasonably include refurbishing all drive mechanisms.

PSC Response: Nine control rod drives and orifice assemblies (CRD0A) including the six that failed to scram on June 23, 1984 have undergone shim motor refurbishment.

Of those nine CRD0A's seven have also undergone 200

. assembly gear train refurbishment.

L1 Plans are to refurbish 37 CRD0As beginning a February 1, 1985 and to be completed prior to restart on April 1, 1985. The seven spare CRDOAs will be refurbished after; restart. A report describing the planned refurbishment aci.ivities will be submitted to the NRC by January 31, 1985.

.b. NRC Finding: Regardless of any other measures taken to remedy the failure to scram problem prior to reactor restart, PSC must outline -and commit- to periodic inspection / preventive maintenance and surveillance

' programs . for control rod drives and associated position instrumentation.

PSC Response: Research into causes of failure and preventive maintenance for' the CRDOAs is in progress. A preventive maintenance program for the control rod drives and associated position instrumentation will be developed and implemented.

Periodic surveillan'ce..bfrodpositionpotentiometersand switches will be developed and implemented in interim procedures.if. feasible..

Both the preventive maintenance program and' surveillance program will be developed and submitted to~_the NRC by-

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January 31,-1985.

c. 'NRC Finding:' implement procedures to. prevent overdriving the control rods past the rod-in limit.

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Attachm:nt to P-85003 Page 2 PSC Response: S0P 12-01 has been revised to address the overdriving of control rods. Formal training on this revised procedure is scheduled to be completed by D January 31, 1985.

d. NRC Finding: One 30-weight percent and one 40-weight percent reserve shutdown hopper should be functionally tested to assure that the reserve shutdown capability is fully available.

PSC Response: Functional testing of two reserve shutdown (RSD) hoppers has been performed. Samples from one 20-weight percent (20 weight percent rather than 30 weight percent is the correct value for the RSD hopper. This was incorrectly submitted in a previous correspondence) and one 40 weight tercent hopper have been obtained. During the functional testing, the 40-weight percent hopper released approximately half of material in the hopper as was reported to the NRC in LER 84-12 dated 12-5-84.

Samples were taken from both the 20-weight percent and 40-weight percent material for examination and analysis to determine the cause and extent of'the problem.

The examination of the RSD balls will be completed and a report prepared for the NRC by January 31, 1985.

e. NRC Finding: Until the long term corrective actions are completed, the licensee should develop a procedure that will require a reactor shutdown under conditions where purge flow is lost or when high levels of moisture exist in the coolant.

PSC Response: The Emergency Procedures are being reviewed for adequacy in addressing a loss of purge flow or a high moisture condition. Investigations into the effects of loss of purge flow and of high PCRV moisture on control rod operability are continuing.

Prior to startup, procedures will be revised or Operations Orders will be issued which ensure operator response to either condition. The response required of the operator will be dependent on the results of the investigations. A report describing the findings will be submitted to the >

NRC by January 31, 1985.  !

f. NRC Finding: Implement a procedure for recording representative samples of CRDM temperatures. at all operating conditions until continuous recording capability k.'

Attachment to P-85003 Page 3 is available.

PSC Response: In the short term, a CRDM temperature readout (not recording) is being installed in the control room. Installation of RTDs in the CRD0As is being performed.

A status report for the NRC and implementation of short term items is scheduled to be completed by January 31, 1985.

II. Actions Rec uired to Correct Weaknesses Noted in the Area of Overall Concuct of Operations NRC Finding: The staff has concluded that PSC must develop a comprehensive program for identifying the underlying causes for the deficiencies and for applying corrective measures. This program should be conducted by a third party consulting organization and should be aimed at reviewing the PSC management structure and practices relative to the operation of FSV with emphasis on correcting deficiencies noted in the various Region IV inspection reports, the last two sal.Ps and programmatic weaknesses identified in Section 4 of this report. PSC should submit the scope and schedule for this program prior to reactor restart.

PSC Response: A program is underway to improve operational and maintenance practices.

A third party consultant is currently in the process of conducting an assessment of PSC management structure and practices relative to Fort St. Vrain. The scope and schedule of this assessment was submitted by PSC on November 26, 1984 (P-84505). Further correspondence on this matter was recently submitted by Mr. R. F. Walker to Mr. R. D. Martin.

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Attachment to P-85003 Page 4 III. Actions Required for the Upgrade of Technical Specifications

a. NRC Findings: A high priority effort should be undertaken to review and propose revisions to the existing Technical Specifications to reduce the likelihood of operator error and/or misinterpretation and correct omissions. The staff has determined that a schedule should be developed by PSC which will reflect completion of the review, revision, and submittal of the proposed Technical Specifications by April 1, 1985.

PSC Response: Revisions to the electrical system technical specifications and plant protective system technical specifications are underway and scheduled to be submitted to the NRC prior to January 31, 1985.

Other Technical Specifications will be revised with a goal of having draft Technical Specifications submitted to the NRC by April 1,1985 for an acceptance review.

The schedule for the Technical Specification Upgrade Program has been-submitted to the NRC by PSC Letter P-84530 dated December 14, 1984.

b. NRC Finding: To improve control rod and reserve shutdown reliability, the licensee shall propose 'the following changes to Technical Specifications, and implement. interim procedures until the Specifications are approved:
1. A weekly control rod exercise surveillance program for all partially inserted or fully withdrawn control rods other than the regulating rod.
2. A Limiting Condition for Operations defining control rod operability and the minimum requirements for rod position indication; and (CL#943(B), 943(C), &

945(B))

3. A Limiting Condition for Operation and a corresponding surveillance test to define and confirm reserve shutdown system operability.

'PSC Response:

1. An interim procedure will be implemented on a weekly basis while control rods are withdrawr. to verify CRD operability for all withdrawn and partially inserted control rods except region I. . This- procedure will likely involve an approximate 6 inch rod drop, with

a Attachment to

. P-85003 Page 5 back-EMF data also collected and analyzed to verify CRD operability. The 6 inch rod drop turns the first gear driven by the motor shaft pinion gear many times thereby satisfying the NRC exercise requirement.

The precedure is scheduled to be implemented April 1, 1985.

2. Investigations are underway to determine appropriate revisions to the Technical Specifications to define control rod operability and minimum requirements for control rod position indication. These Technical Specification requirements w'll be submitted to the NRC as part of the Technical Specification Upgrade Program.

Interim procedures will be implemented that verify control rod operability and the minimum requirements for control rod position indication.

These interim procedures are scheduled to be in place by April 1, 1985. Documentation of investigation results will be submitted by January 31, 1985 as part of the overall CRD operability report.

3. Procedures are in existence that define reserve shutdown system operability. Inspection of the boron balls will be perfomed under item I.d above. SR 5.1.2-R will be revised to include a physical examination of the reserve shutdown material in the interim.

Appropriate technical specification revisions will be submitted to the NRC as part of the Technical Specification Upgrade-Program.

LIV. Actions Required on Continued Water Ingress

a. NRC Finding: In the area of continued water ingress the staff has determined that PSC must develop a plan to carry out any of those modifications recomended by the PSC

" Moisture Ingress Committee" that are determined by PSC to have a high potential to significantly reduce the frequency and severity of upsets involving injection of circulator bearing water into the helium coolant. Any

. significant reduction would clearly reduce the frequency of plant transients; improve the reliability of overall plant operations;' and might, if moisture has an effect, improve the performance of control rod drives. This plan

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Attachment to P-85003 Page 6 should include a status report to the NRC as part of the annual report on the progress in implementing modifications.

PSC Response: Thirteen of twenty recently approved recomendations of the Moisture Ingress Comittee (now the FSV Review Comittee) have been completed.

A plan will be developed to further implement approved recomendations of the FSV Review Comittee. The potential for significantly reducing the frequency, severity, and consequences of upsets involving moisture will be the basis for implementation of such recomendations.

An annual status report on progress in reducing moisture ingress will be provided to the Nuclear Regulatory Commission. The first annual report is scheduled for submittal to the NRC April 1, 1985.

V. The Following Actions Should Be Completed Following Restart:

a. NRC Finding: In addition to the above items required for restart, the staff noted several weaknesses that should be corrected on a longer term basis. The licensee must submit schedules within 60 days of restart for completing these items.

PSC Response: Schedules for completion of long term items will be submitted to the NRC within 60 days after restart.

b. NRC Finding: Provide continuous recording of a representative sample of CRDM temperatures at all operating conditions to provide part of the data necessary for the longer term program.

PSC Response: Designs are being investigated for providing continuous temperature recording for a representative sample of CRDM temperatures. A report will be submitted on these results by January 31, 1985.

c. NRC Finding: Determine whether compensating design and/or operational modifications are needed to minimize moisture ingress to the CRDM cavities and minimize temperatures in the vicinity of the rod drives. In the event that temperatures recorded during plant operation prove to be higher than those for which the assembly was initially qualified, take imediate steps to perform environmental requalification testing of a CRDM assembly or hold -

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.4 Attachment to P-85003 Page 7 temperatures to that for which the CRDM has been qualified.

PSC Response: Compensating design and operational modifications are being evaluated. The installation of seals is being reviewed to determine the effects of their presence in removing moisture from the CRD0A motor area following events where high primary coolant moisture levels are present.

In the event that CRDOA temperatures recorded during plant operation prove to be higher than the present qualification temperature, 272 degrees F, imediate steps will be taken to perform environmental requalification testing on a CRD0A motor assembly. During requalification, plant operation will be restricted in order to maintain CRDM temperatures below 272 degrees F.

However, CRD0As instrumented with temperature devices have been monitored for years and a problem is not expected.

An administrative limit of 250 degrees F is currently in effect at which point Station Manager approval is required to continue operation.

d. NRC Finding: The present Watt-meter testing of the shim motor during drive-in and drive-out is not a reliable method .to verify full insertion or withdrawal of control rods. This test should be refined or an alternative, reliable test for control rod position verification developed.

PSC Respons(: The methodology for the Watt-meter testing referred to is technically. sound. A procedure to more precisely describe the process and provide instructions on

.how to interpret the data has been prepared. In addition, methods of increasing the sensitivity of the recording instrumentation are being evaluated. A report on this acitivity will be submitted to the NRC by January 31, 1985.

e. NRC Finding: Investigate a design change to provide a positive stop on the CRDM position indicator potentiometer shaft to prevent overtravel and provide the results to the NRC.

PSC Response: The concept.of either a positive stop or an alternate type of position potentiometer is being

-considered. The problem is that overtravel of the control rod damages the existing position potentiometers resulting

. in loss of position indication. Preliminary results favor u a} % &- eAeJt w k gj u % a p d.k sb p.

(i%)% p e6 ceW t/9/6s.)

Attachment to P-85003 Page 8 Investigations and design efforts are targeted for completion by January 1, 1986. Installation of modifications will be accomplished during future preventive maintenance activities,

f. NRC Finding: Conduct an integrated systems study to

-resolve rod position indication, maintenance and operability questions.

PSC Response: An . integrated systems study will be conducted to identify state-of-the art control rod position indication systems that could be used on the Fort St. Vrain CRD0As to improve. indication reliability under all expected environmental conditions. This study is targeted for completion June 30, 1986.

g. NRC Finding: Establish procedures for verification and sign-off by the Maintenance Quality. Control (MQC) of key steps in Technical Specification surveillance procedures..

PSC Response: Quality Assurance pr cedures will be implemented to provide for verification and signoff by Maintenance -Quality Control of key steps in Technical Specification surveillance procedures. Completion of this activity is targeted for January 1,1986.

h.- NRC Finding: Establish a procedure for review and concurrence by the QA organizatian of safety-related procedures and changes thereto.

PSC Res)onse: Quality Assurance procedures are being establis1ed and Administrative Procedure G-2 is being revised to provide for QA review and concurrence of safety related procedures. Full implementation of .this program is targeted for January 1,1986.

i. NRC Finding: At the time of the audit, the MQC group was reviewing each completed surveillance procedure. The staff concluded that this practice 'should continue.

PSC Response: A formal program will be implemented to provide for Maintenance Quality' Control review of completed Technical Specification surveillance test procedures. Implementation of this program is targeted for July 1,1985.

j. NRC Findinc : A review by the QA organization of the content anci adequacy of the Technical Specification

,.t Attachment to P-85003 Page 9 procedures is important, and the staff has determined that this'should be implemented.

PSC Response: Scope of potential criterb for the Quality Assurance review process of the Teche; cal Specification procedures is being discussed within Public Service Company.

The Quality Assurance review of Technical Specification Surveillance Test procedures, excluding the Environmental Surveillance Requirements (ESRs), will begin in conjunction with the implementation phase of the new or revised test procedures. Full implementation of the QA review noted above is targeted for January 1,1986.

VI. Additional Items to be Addressed

a. NRC Finding: Chemically analyze and evaluate the debris and rust on the CRDMs as to particulate size and composition. Characterize and analyze the motor bearing debris found during ultrasonic cleaning.

4 PSC Response: Two additional samples of " Debris" have

- been analyzed. Rust will be analyzed in the near future.

Attempts are being made to obtain a particulate size analysis.

Given the methods that must be utilized to obtain bearing debris and the small quantity of the sample, particulate size analysis may not be possible. Likewise particulate size analysis of the rust on the CRDM will not be meaningful or representative because of the methods that must be used to obtain the sample.

The composition analyses will be completed by January 18, 1985. Documentation on the composition analyses and any size analyses available will be submitted at that time.

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